1. Field of the Invention
The subject invention is directed to a balancing system for a gimbal assembly, and more particularly, to a center of mass balancing system for an optical gimbal assembly which is guided by active feedback derived from an inertial measurement unit associated with the gimbal.
2. Description of Related Art
Gimbals are often used for mounting optical instrumentation and sensors used in airborne surveillance applications including, for example, airborne law enforcement, pipe and power line inspection, mapping, and intelligence, surveillance and reconnaissance missions. The optical instrumentation can include sensors for thermal imaging, as well as laser range finders and illuminators.
It is important for the gimbal to be perfectly balanced about its rotation axes in order to prevent drift, which may affect the accuracy of the system. This is particularly important when the gimbal is used for imaging or targeting on an airborne platform, where such an error can have a cumulative effect.
It is extremely difficult to machine gimbal components to obtain perfect balance due to limitations of the machine tools used in the manufacture of the components. Accordingly, gimbal balancing devices are often provided to remedy this inherent defect. In general, these balancing devices attempt to position a mass relative to the gimbal axes, which is adapted to rotate with the gimbal in order to shift the gimbal center of gravity.
Presently available gimbals equipped with these balancing devices have had limited success, since they typically require direct access to the balancing device and to the gimbal. Under these conditions, once a gimbal has been properly balanced and enclosed in a protective housing, direct access to correct any subsequent imbalance in the system can be difficult.